In wireless communications systems, obtaining reliable high-speed communications poses a number of problems for the wireless channel. The signal transmitted over the wireless channel is subject to multi-path distortion which may significantly affect the amplitude and phase of the transmitted signal. Forward error control (FEC)/channel codes are widely used to reduce transmission errors in a radio channel subject to fading. There are many types of conventional FEC/channel codes having error correction capabilities, for example, convolutional codes, block codes, Hamming codes and turbo codes.
The choice of FEC/channel codes will depend on the required quality of service determined by, for example, the data rate, delay rates and error rates, and the radio channel. Typically, different FEC/channel codes will be employed in different standards as different standards will have different target applications and therefore different quality of service (QOS) requirements. However, it may be desired to support, within the same standard, a set of FEC/channel codes providing different coding gains for different services.
To support multiple FEC/channel codes, one commonly used conventional method is to employ multiple encoders in the transmitter and multiple decoders in the receiver. However, this has the disadvantage of requiring the communication equipment to be extremely complex.
Thus, there is a need to provide a coding/decoding (CODEC) system and process for use with multiple FEC/channel codes which is less complex and more economical than conventional systems and methods.